Validating a Mixed Qualitative Behavioral Assessment for Adult Western Lowland Gorillas ( <i>Gorilla gorilla gorilla</i> ) II: Significant Event Monitoring

ABSTRACT The Gorilla Behavioral Assessment Tool (GBAT) is the first of a new class of research and welfare tools termed mixed qualitative behavioral assessments or M‐QBAs. An M‐QBA is a unique tool that integrates the affective welfare indicators of classic QBAs with the behavioral and physiological indicators of typical welfare assessments to create a more comprehensive whole animal tool. Previous validation efforts for the GBAT during baseline conditions (Part I) have established high inter‐rater agreement across raters, subjects, and institutions as well as strong or preliminary construct validity for seven of the 12 tested items. Our second validation focused on a significant life event, specifically an inter‐institutional transfer of two groups ( n = 6) of western lowland gorillas ( Gorilla gorilla gorilla ) between the Cincinnati Zoo &amp; Botanical Garden and the Detroit Zoo. Both teams collected behavioral data and fecal samples in addition to daily completion of the GBAT. We used Gwet's AC 2 to establish near‐perfect inter‐rater reliability and Spearman's correlations and generalized linear mixed models to assess construct validity. We validated all 12 of the tested items, including the 7 items previously validated in Part I. Across both validation efforts, we have demonstrated high, consistent inter‐rater reliability, including application both for adult males and a small sample ( n = 2) of adult females. We have also established significant or preliminary construct validity for all tested items. Ultimately, we present the GBAT as a welfare and research tool with promising validation results as a model for future M‐QBAs.